Fast macroblock mode decision algorithm for B frame in AVS

In order to reduce the computational complexity of macroblock(MB) mode decision for B frame in AVS(Audio Video Coding Standard),a fast strategy for B frame MB mode decision based on RDO(Rate-Distortion Optimization) technique is proposed.According to the characteristics of eyes which are sensitive to edge,a visual threshold mode is proposed. Edge information of an MB is extracted by sobel operator,which is then applied to visual threshold mode to get the edge modes of an MB.Edge mode is chosen based on the analysis of the grain complexity of one MB from both the horizontal and vertical directions,in order to get fast strategy of MB partition mode decision.And the intra mode decision algorithm is proposed based on the temporal and spatial correlation.Experimental results show that the new algorithm reduces computational time by 40%,with slight increment of bit-rate and little loss of peak signal-to-noise ratio.